AFM ADJUSTMENT w/o gas analyzer

airkooledchris · Post by **airkooledchris** » Fri Jan 09, 2009 5:07 pm

im taking measurements while driving...

I do my setting up with the meter at idle obviously, which isn't under load so I always have to take a trip and see where im actually at.

I think I just removed a vacuum leak which was likely throwing it all off, so im going to head out tonight again and see if I can't get it close.

airkooledchris · Post by **airkooledchris** » Tue Jan 20, 2009 2:46 pm

getter closer.

a recent long trip I took got me about 14.5 MPG highway, which is the best ive seen since this rebuild.

may have had an small exhaust leak at the neck of the muffler after the headers, which may have tweaked my LM-1 readings.
going out tonight to put the now-repaired exhaust back on and see where im at.

reluctantartist · Post by **reluctantartist** » Fri Apr 03, 2009 8:27 pm

I have been reading this thread and wanted to know peoples thoughts on using he oxygen sensor for checking AFM. The bosch fuel injection manual talks about doing this. I have an 1982 California L-Jet with Lambda sensor. I am not sure trying to adjust the wiper would be any good with this setup since the lambda corrects things.

Thanks

Post by **Amskeptic** » Fri Apr 03, 2009 8:46 pm

reluctantartist wrote:I have been reading this thread and wanted to know peoples thoughts on using he oxygen sensor for checking AFM. The bosch fuel injection manual talks about doing this. I have an 1982 California L-Jet with Lambda sensor. I am not sure trying to adjust the wiper would be any good with this setup since the lambda corrects things.

Thanks

I am a politically and environmentally incorrect opponent of Lamba-controlled fuel injection on an air-cooled engine. What makes the exhaust valves happy. . . makes me happy. That is 13.5:1 under load.
Colin

reluctantartist · Post by **reluctantartist** » Sat Apr 04, 2009 6:43 am

So you are saying I am sort of screwed with my lambda system. There is no way for me to get my 13:5:1 ration with it? I actually just want the ratio that is best for MPG 1st and then exhaust valves. Are there any tweaks I can do with the Lambda system?

Post by **Amskeptic** » Sat Apr 04, 2009 1:05 pm

reluctantartist wrote:So you are saying I am sort of screwed with my lambda system. There is no way for me to get my 13:5:1 ration with it? I actually just want the ratio that is best for MPG 1st and then exhaust valves. Are there any tweaks I can do with the Lambda system?

It will forever be trying to keep you near stochiometric. It is a worthy system, and it is lovely for catalytic converters, but I do not like it for air-cooled freeway hot cruising. I would like a day of LM-1 testing with it before I would ever tell others what they should or should not do.
Colin

Randy in Maine · Post by **Randy in Maine** » Sat Apr 04, 2009 3:10 pm

If it is any help, my LM-1 will be visitng Ryan out there in Indiana after it gets back from Nova Scotia in about 6 weeks after I am done with it here.

Perhaps you Hoosiers can work on them together.

By the way, the LM-1 gets around a lot more than I do anymore.

Gypsie · Post by **Gypsie** » Sun Apr 05, 2009 1:56 pm

I had to back up from using the LM-1 readings I got before. I had read somewhere that the Cat shouldn't effect the reading too awful much and that it would show a tad leaner than actual as I was reading post cat.

I went straight to Colin's wiper method and have been fine tuning. I really should get a bung welded for proper LM1 readings. Considereing I had to Borrow Westy78/IFBWax's unit for the testing I figger I better work it out witout the sensor since I don't have ready usage all the time.

I see it as a nice way to bring it in close and then use fine tuning adj skills to tighten the mix.

Colin's method leaves it a tad rich but you can adj that richness away with minute adjustments.

I have actually enjoyed this method as it has mede me think on what the afm is doing and how my adjustments are impacting performance.

Still only getting 13-16mpg in the van though. RRRRR!

Automatic 2L Vanagon running at 95-105 compression.

Thinking the rings I did last summer just bought a little time. Pistons and Cylindars all around next time.

hambone · Post by **hambone** » Sun Apr 05, 2009 2:00 pm

I think 16 mpg is a gold mine with a fully laden AC Vanagon with a slightly elderly engine. Not to mention auto trans.
But whatta I know?

reluctantartist · Post by **reluctantartist** » Sun Apr 05, 2009 7:02 pm

Randy, where is Ryan located? I would be interested.

Thanks

Randy in Maine · Post by **Randy in Maine** » Sun Apr 05, 2009 7:26 pm

IU Bloomington. You could hit his house with a rock I will bet.

I U is actually a pretty decent school and is one of the "public ivy" schools.

Itinerant Air-Cooled

Itinerant Air-Cooled

AFM ADJUSTMENT w/o gas analyzer